Abstract: Variability in fungal features in 30 isolates of C. gloeosporioides f. sp. manihotis Henn (Penz). Sacc (causal organism of cassava anthracnose disease CAD), from seven cassava growing regions of Nigeria (Oyo, Ogun, Ondo, Osun, Plateau, Kwara and Cross River State), where the disease is prevalent, were investigated on the basis of culture, morphology and pathogenicity. Culture and morphology showed variations in mycelial pigmentation, growth media colour, radial growth pattern, presence or absence of setae and acervuli production amongst isolates. Spore morphology differed (P<0.05) in conidial length, spore density, germ-tube development. Pathogenicity test showed significant differences (P<0.05) in virulence amongst the isolates. All thirty isolates were pathogenic to two test cassava genotypes, causing necrotic lesions after artificial inoculation by stem puncture. Fungal isolates 05, 10 and 26 were more virulent, causing lesion size exceeding 20 mm in susceptible test cassava genotypes at 21 days after inoculation. The relationship among fungal growth parameters (mycelial growth, conidial length, spore germination and sporulation density) and virulence of the fungal isolates, showed a significant positive correlation between spore germination and sporulation (r=0.72), spore germination and virulence (r=0.76). Sporulation was significantly correlated with virulence (r=0.83), but not correlated with conidial length (r=0.19).